[ECR] [request]: sourceIPAddress field in CloudTrail Logs

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**Tell us about your request**
All push/pull actions performed against a repository record the sourceIPAddress field in CloudTrail as "AWS Internal". this is because (to the best of my understanding) the repository itself is a different service, and is essentially proxying the requests. As we make greater efforts to control our supply chain, not being able to reliably track source IPs for code commits is causing issues for us.

**Which service(s) is this request for?**
ECR

**Tell us about the problem you're trying to solve. What are you trying to do, and why is it hard?**
We are planning to leverage Registry Policies to create allow/deny lists for Push actions against the repositories. With some research and some help from AWS support, we found that this is indeed possible, however the source IP address of those requests is not recorded. As you can imagine, if you are going to be installing an allow list filter on an in-use service, it's very important to be able to assert that the lists you are about to install will not break existing work flows, and log analysis is one of the best ways to do this. additionally, once installed, troubleshooting failures would rely HEAVILY on being able to reliably determine the source IP.

**Are you currently working around this issue?**
I dont have a good work around at the moment. Technically we can get to the end state we need to be in, but the lack of visibility for source IPs creates a significant blind spot for monitoring, as well as a huge troubleshooting problem, that we dont have a work around for.

The request concerns ECR push and pull actions whose CloudTrail sourceIPAddress is recorded as "AWS Internal". No repository files, tests, or implementation entry points are identified, so start by reviewing the ECR and CloudTrail behavior described in the issue. Done would require source IP visibility that can support registry-policy validation and troubleshooting.

Written by the indexing model from the issue text.